Rational Design of Dimensionally Stable Anodes for Active Chlorine Generation

Abstract

RuO2 is one of the most important electrocatalyst materials as a key component of dimensionally stable anode (DSA) for chlorine evolution reaction, because of the high catalytic activity, while anodic corrosion remains a fundamental challenge that must be addressed. Here, we demonstrate that low-temperature annealing of RuO2 nanoparticles (∼1.7 nm) supported on Nb-doped TiO2 leads to the formation of durable active sites with superior activity and product selectivity toward active chlorine generation (10 mA cm–2 at 22 mV overpotential with a Faradaic efficiency of 97.3% in 0.6 M NaCl, which is much better than that of commercial DSA). The Nb doping not only enhances the electronic conductivity of TiO2 support, but also enables thermal diffusion of Ti atoms into the RuO2 lattice at only 200 °C, forming ultrafine solid-solution nanoparticles with ultrathin TiO2 surface as a protective layer. This work provides a cost-effective fabrication strategy of stable RuO2 electrocatalysts for anodic reactions, as well as additional insights into the design principle of DSA.

Niobium K-Edge X-ray Absorption Spectroscopy of Doped TiO2 Produced from Ilmenite Digested in Hydrochloric Acid

“…Other uses for Nb-doped TiO 2 include photovoltaics and dye-sensitized solar cells. − It also finds application in photocatalysis including for the production of H 2 , photoelectrochemical water splitting, and photocatalytic CO 2 reduction . Other catalytic applications are for catalyst supports, for example, for the oxygen reduction reaction and H 2 production, or for dimensionally stable anodes for the chlorine evolution reaction, and electrochemical destruction of “forever chemicals” . Nb-doped TiO 2 has potential application in batteries and supercapacitors including lithium-ion batteries , and Na-ion batteries .…”

Visualization of Electrochemically Accessible Sites in Flow-through Mode for Maximizing Available Active Area toward Superior Electrocatalytic Ammonia Oxidation

“…The crystal structure of the active coating was investigated by XRD (Figure e). Compared with Ti substrate, the additional diffraction peaks of the Ti/RuO 2 porous electrode are attributed to rutile RuO 2 and TiO 2 . The detailed structural information on the coating was further investigated by TEM and SEAD.…”

“…Compared with Ti substrate, the additional diffraction peaks of the Ti/RuO 2 porous electrode are attributed to rutile RuO 2 and TiO 2 . 32 The detailed structural information on the coating was further investigated by TEM and SEAD. The lattices with different structural orientations obtained from the TEM image were assigned to TiO 2 (110) and RuO 2 (101) planes (Figure 3f), and the SAED pattern also revealed that the diffraction spots corresponding to the TiO 2 (110) and RuO 2 (101) planes were clearly visible (SI Figure S12).…”

Tip-Intensified Interfacial Microenvironment Reconstruction Promotes an Electrocatalytic Chlorine Evolution Reaction

“…By precisely regulating the fabrication parameters (Table S1), we constructed three kinds of nanostructure-decorated electrodes, including a slab with a large curvature radius of ∼200 nm, nanorods with a curvature radius of ∼25 nm, and nanoneedles with a small curvature radius of ∼10 nm (Figure a–c). As presented by the X-ray diffraction (XRD) pattern, some additional diffraction peaks of the electrodes were assigned to rutile TiO 2 and RuO 2 (Figure d) …”

“…As presented by the X-ray diffraction (XRD) pattern, some additional diffraction peaks of the electrodes were assigned to rutile TiO 2 and RuO 2 (Figure 1d). 17 EDX exhibited a homogeneous distribution of Ti, O, and Ru on the surfaces of the electrodes (Figure 1e). Because the thickness of magnetron-sputtered Ru was only 20 nm, the EDX mapping signal of Ru was visibly weaker than that of Ti, with a Ru content of ∼0.2 g m −2 in the three electrodes.…”